The Biochar Derived from Carp for High‐Efficiency Solar Steam Generation and Water Purification

Efficient utilization of solar energy to generate steam is a green and promising technology because of its great potential applications in seawater desalination and industrial wastewater purification. However, the practical application of high‐efficiency solar steam generation devices is largely overshadowed due to their complex process, high cost, low life‐span, and poor thermal performance. Here, novel meat and bonemeal biochar (MBB) with high solar steam generation efficiency is produced by pyrolyzing dead carp at 300, 400, and 500 °C under anoxic conditions. Attributed to its typical hydrophilic pore structure, the photon trapping ability of MBB500 is up to 97% and 84.1% in the ultraviolet and visible regions and near‐infrared light regions, respectively. Meanwhile, hydrophilic pore structural provides a strong capillary force for the rapid transmission of water. As a result, under 1 sun illumination (1 kW m(−2)), the water evaporation rate and the apparent energy conversion efficiency of MBB500 reach 1.48 kg m(−2) h(−1) and 131.2%, respectively. In addition, MBB500 also exhibits excellent seawater and heavy metal wastewater evaporation effects, providing a new manufacturing strategy for photo‐thermal materials, which greatly benefit their practical application in pure water regeneration.